To date, quantitative analysis of proanthocyanidin (PAC) containing materials including plant extracts and fractions depends on colorimetric assays or phloroglucinolysis/thiolysis combined with UV-HPLC analysis. Such assays are of limited accuracy, particularly lack specificity, require extensive sample preparation and degradation, and need appropriate physical reference standards. To address this analytical challenge and toward our broader goal of developing new plant-sourced biomaterials that chemically and mechanically modulate the properties of dental tissue for clinical interventions, we have characterized 12 different PAC DESIGNER (Depletion and Enrichment of Select Ingredients Generating Normalized Extract Resources) materials.
View Article and Find Full Text PDFThis exploratory study was designed to identify factors implicating microbial influence on medicinal plant metabolomes. Utilizing a whole-microbiome approach, amplicon sequencing was used to identify the makeup of fungal and bacterial assemblages from endophytic (interior) and epiphytic (external) environments in two different sets of congeneric host-plant pairs, with collection of multiple samples of two medicinal plant species () and two generic analogs (). Diversity analysis of microbial assemblages revealed the influence of three primary factors driving variance in microbial community composition: host-plant taxonomy, the compartmentalization of microbial communities within discrete plant parts, and the scale of distance (microhabitat heterogeneity) between sampling locations.
View Article and Find Full Text PDFObjective: Investigate the bioactivity and stability of Rhodiola rosea (RR) fractions as a natural source of prodelphinidin gallate (PDg) on dentin collagen via analysis of the viscoelastic and resin-dentin adhesive properties of the dentin matrix.
Methods: The biomimicry and stability of RR subfractions (F1, F2, F3 and F4) with collagen were determined by dynamic mechanical analysis (DMA). DMA used a strain sweep method to assess the dentin matrix viscoelastic properties [storage (E'), loss (E"), and complex (E*) moduli and tan δ] after treatment, 7-, 30- and 90-days of storage in simulated body fluids (SBF).
Quantum mechanics (QM)-driven terative unctionalized pin nalysis produces HifSA profiles, which encode the complete H spin parameters ("nuclear genotype") of analytes of interest. HifSA profiles enable the establishment of digital reference standards (dRS) that are portable, FAIR (findable - accessible - interoperable - reusable), and fit for the purpose of quantitative H NMR (qHNMR) analysis at any magnetic field. This approach enhances the sustainability of analytical standards.
View Article and Find Full Text PDFBackground: Coercion perceived by psychiatric inpatients is not exclusively determined by formal measures such as involuntary admissions, seclusion or restraint, but is also associated with patients' characteristics and professionals' attitude.
Aims: This study examined how inpatients' involvement in the decision making process, the respect of their decision making preference, and their feeling of having been treated fairly mediate the relationship between involuntary hospitalisation and perceived coercion both at admission and during hospital stay.
Methods: Mediation analysis were performed in order to study the relationship between involuntary hospitalisation and perceived coercion among 230 patients, voluntarily and involuntarily admitted in six psychiatric hospitals.
Three unique linear oligomeric depsipeptides, designated as cavomycins A-C (-), were identified from , a gut bacterium associated with the annelid . The structures of these depsipeptides were determined through a combination of spectroscopic methods and chemical derivatization techniques, including methanolysis, the modified Mosher's method, advanced Marfey's methods, and phenylglycine methyl ester derivatization. The unique dipeptidyl residue arrangements in compounds - indicate that they are not degradation products of valinomycin.
View Article and Find Full Text PDFJ Biomed Mater Res B Appl Biomater
January 2024
Flavan-3-ol monomers are the building blocks of proanthocyanidins (PACs), natural compounds from plants shown to mediate specific biologic activities on dentin. While the stereochemistry of the terminal flavan-3-ols, catechin (C) versus epicatechin (EC), impacts the biomechanical properties of the dentin matrix treated with oligomeric PACs, structure-activity relationships driving this bioactivity remain elusive. To gain insights into the modulatory role of the terminal monomers, two highly congruent trimeric PACs from Pinus massoniana only differing in the stereochemistry of the terminal unit (Trimer-C vs.
View Article and Find Full Text PDFProanthocyanidins (PACs) are complex flavan-3-ol polymers with stunning chemical complexity due to oxygenation patterns, oxidative phenolic ring linkages, and intricate stereochemistry of their heterocycles and inter-flavan linkages. Being promising candidates for dental restorative biomaterials, trace analysis of dentin bioactive cinnamon PACs now yielded novel trimeric ( and ) and tetrameric () PACs with unprecedented - and benzoquinone motifs (benzoquinonoid PACs). Challenges in structural characterization, especially their absolute configuration, prompted the development of a new synthetic-analytical approach involving comprehensive spectroscopy, including NMR with quantum mechanics-driven H iterative functionalized spin analysis (HifSA) plus experimental and computational electronic circular dichroism (ECD).
View Article and Find Full Text PDFGiven that the essence of Science is a search for the truth, one might expect that those identifying as scientists would be conscientious and observant of the demands this places on them. However, that expectation is not fulfilled universally as, not too surprisingly, egregious examples of unethical behavior appear and are driven by money, personal ambition, performance pressure, and other incentives. The reproducibility-, fact-, and truth-oriented of Science has come to face a variety of challenges.
View Article and Find Full Text PDFIn botanical extracts, highly abundant constituents can mask or dilute the effects of other, and often, more relevant biologically active compounds. To facilitate the rational chemical and biological assessment of these natural products with wide usage in human health, we introduced the DESIGNER approach of Depleting and Enriching Selective Ingredients to Generate Normalized Extract Resources. The present study applied this concept to clinical Red Clover Extract (RCE) and combined phytochemical and biological methodology to help rationalize the utility of RCE supplements for symptom management in postmenopausal women.
View Article and Find Full Text PDFBackground: Asthma is not well investigated in equatorial Africa and little is known about the disease-associated allergen molecules recognized by IgE from patients in this area. The aim was to study the molecular IgE sensitization profile of asthmatic children and young adults in a semi-rural area (Lambaréné) of an equatorial African country (Gabon), to identify the most important allergen molecules associated with allergic asthma in equatorial Africa.
Methods: Fifty-nine asthmatic patients, mainly children and few young adults, were studied by skin prick testing to (Der p), (Der f), cat, dog, cockroach, grass, Alternaria and peanut.
Breast cancer risk continues to increase post menopause. Anti-estrogen therapies are available to prevent postmenopausal breast cancer in high-risk women. However, their adverse effects have reduced acceptability and overall success in cancer prevention.
View Article and Find Full Text PDFMonoterpenoids are integral to the chemical composition of the widely used adaptogenic dietary supplement . The present study expands the chemical space and stereochemical information about these taxon-specific constituents from the isolation and characterization of five geraniol-derived glucosides, -. While and exhibited almost identical NMR spectra and shared the same 2D structure ascribed to the 4-hydroxygeraniolglucoside previously described as rosiridin, the NMR-based Mosher ester method revealed the enantiomeric nature of their aglycone moieties.
View Article and Find Full Text PDFVegetables provide important nutrients but can also induce allergic symptoms. Celery tuber allergy frequently occurs in Central European countries and can cause allergic reactions including fatal anaphylactic shocks. There is little information about allergen content in seeds.
View Article and Find Full Text PDFInvestigation of a pine bark extract for bioactive proanthocyanidin oligomers resulted in the isolation of structurally related dimeric B-type procyanidin derivatives, -. This includes scalemic mixtures of gambiriin A1 () and A2 () and their newly described optical antipodes, -gambiriin A1 () and -gambiriin A2 (), respectively, as well as a racemic mixture of the newly described (-)gambiriin A5 (/). Furthermore, the study now fully characterizes the previously reported optically pure dimers gambiriin B1 () and gambirflavan D1 (), and characterized the novel B-type procyanidin trimer, (gambirifuran C1).
View Article and Find Full Text PDFLicorice, the roots and rhizomes of L., has been used as a medicinal herb, herbal adjuvant, and flavoring agent since ancient times. Recently, licorice extracts have become popular as dietary supplements used by females to alleviate menopausal symptoms.
View Article and Find Full Text PDFBackground: Network meta-analysis is a method that can estimate relative efficacy between treatments that may not have been compared directly within the literature. The purpose of this study is to present a network meta-analysis of non-conventional interventions to improve upper extremity motor impairment after stroke.
Methods: A literature search was conducted in 5 databases from their inception until April 1, 2021.
Biological nitrogen fixation (BNF) is a key process for the N input in agriculture, with outstanding economic and environmental benefits from the replacement of chemical fertilizers. However, not all symbioses are equally effective in fixing N, and a major example relies on the high contribution associated with the soybean (, contrasting with the low rates reported with the common bean () crop worldwide. Understanding these differences represents a major challenge that can help to design strategies to increase the contribution of BNF, and next-generation sequencing (NGS) analyses of the nodule and root microbiomes may bring new insights to explain differential symbiotic performances.
View Article and Find Full Text PDFFour new rufomycins, compounds -, named rufomycins 56, 57, 58, and 61, respectively, exhibiting new skeletal features, were obtained from strain MJM3502 and were fully characterized. Compounds and possess a 4-imidazolidinone ring not previously encountered in this family of cyclopeptides, thereby resulting in a [5,17] bicyclic framework. The in vitro anti- potency of compounds and is remarkable, with minimum inhibitory concentration values of 8.
View Article and Find Full Text PDFTo enable translational studies, a scalable preparative isolation scheme was developed for underivatized cocoa () proanthocyanidins (PACs), affording six all-B-type oligomeric PACs, including a new tetramer . Their structures, including absolute configuration, were unambiguously established by comprehensive spectroscopic and chemical methods. Evaluation of the PACs' dentin biomodification properties employed dynamic mechanical and infrared spectroscopic analyses in dentin bioassay models.
View Article and Find Full Text PDF